People have an innate metric for "this thing is slow", it's when lots of time passes between its start and end. Why is color-coding more evident than our own perception of time?
I think his key phrase is "expected to load," which means the color coding would provide an indicator before the user clicks on the links. Therefore, the user skips the unnecessary pain of perceiving the slowness for himself.
The problem is the same as "Downforeveryoneorjustme". Just because a site is loading slow once or twice doesn't necessarily mean that it's the site's fault, it could be any number of issues. But by crowdsourcing this data the truth is revealed.
